Rozwiązane

8. Rozwiąż równanie
a) 1/2y+3=7
b) 1/7y - 5/7 =2
c) 1/4y+3/4=7/4
d) 7/9(y+2)=7/9
e) 2/3(y-1)=2/3
f) -5/11(y-4)=5/11

SZYBKOO! BŁAGAM !!
DAJĘ NAJ ​​



Odpowiedź :

Odpowiedź:

a)

1/2y+3=7

1/2y = 7 - 3     /*2

y = 4 * 2 = 8

b)

1/7y - 5/7 = 2

1/7y = 2 + 5/7     /*7

y = 7(2 5/7) = 7 * 19/7 = 19

c)

1/4y+3/4=7/4

1/4y = 7/4 - 3/4       /*4

y = 4 * 4/4 = 4

d)

7/9(y+2)=7/9

7/9y + 14/9 = 7/9

7/9y = 7/9 - 14/9     /*9/7

y = 7/9 * 9/7 = 1

e)

2/3(y-1)=2/3

2/3y - 2/3 = 2/3

2/3y = 2/3 + 2/3    /*3/2

y = 4/3 * 3/2 = 2

f)

-5/11(y-4)=5/11

-5/11y + 20/11 = 5/11

-5/11y = 5/11 - 20/11       /*(-11/5)

y = -15/11 * (-11/5) = 3

Szczegółowe wyjaśnienie:

Magda

Odpowiedź:

[tex]a)\\\\\frac{1}{2}y+3=7\ \ /\cdot2\\\\y+6=14\\\\y=14-6\\\\y=8\\\\\\b)\\\\\frac{1}{7}y-\frac{5}{7}=2\ \ /\cdot7\\\\y-5=14\\\\y=14+5\\\\y=19\\\\\\c)\\\\\frac{1}{4}y+\frac{3}{4}=\frac{7}{4}\ \ /\cdot4\\\\y+3=7\\\\y=7-3\\\\y=4[/tex]

[tex]d)\\\\\frac{7}{9}(y+2)=\frac{7}{9}\ \ /:\frac{7}{9}\\\\y+2=1\\\\y=1-2\\\\y=-1\\\\\\e)\\\\\frac{2}{3}(y-1)=\frac{2}{3}\ \ /:\frac{2}{3}\\\\y-1=1\\\\y=1+1\\\\y=2\\\\\\f)\\\\-\frac{5}{11}(y-4)=\frac{5}{11}\ \ /:\frac{5}{11}\\\\-(y-4)=1\\\\-y+4=1\\\\-y=1-4\\\\-y=-3\ \ /\cdot(-1)\\\\y=3[/tex]